CXCL1 and kidney failure: Moreover, after adjusting for well-established risk factors for IgAN (including baseline proteinuria, SBP, eGFR, tubular atrophy and interstitial fibrosis, and steroid or other immunosuppressive therapy), higher levels of urinary CXCL1 persistently showed significantly greater risk of kidney failure (HR, per s.d. increment of natural log–transformed CXCL1: 1.748; 95% CI: 1.222–2.499, P = 0.002, Table 5).